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The combustion of the fuel inside a combustor is a complicate chemical phenomena where conversion of chemical energy of the species into the heat energy takes place by burning in the presence of oxygen but in case of the incomplete combustion the unburnt hydrocarbons are evolved as the emissions from the combustors which effects the environment and the efficiency of the combustion also decreases when there is incomplete combustion of the fuel. The present study is performed on an industrial axi-symmetrical combustor using two different fuels and the performance of the combustor is studied to reduce the emissions from the fuel.

Research on carbon material-based thin films with low light reflectance has received significant attention for the development of high absorber coatings for stray light control applications. Herein, we report a method for the successful fabrication of stable thin films comprised of carbon nanotubes (CNTs) and nanoscrolls (CNS) on an aluminium (Al) substrate, which exhibited low reflectance of the order of 2–3% in the visible and near-infrared (NIR) spectral bands. Changes in the structural and chemical composition of pristine single-walled carbon nanotube (SWCNT) samples were analyzed after each processing step. Spectroscopy, microscopy and microstructural studies demonstrated emergence of CNS and multi-walled carbon nanotubes (MWCNTs) due to the sequential chemical processing of the sample. Transmission electron microscopy (TEM) and scanning electron microscopy (SEM) studies revealed the formation of CNS via curling and folding of graphene sheets. Microstructural investigations including SEM and atomic force microscopy (AFM) confirmed the presence of microcavities and pores on the surface of the film. These cavities and pores significantly contribute to the observed low reflectance value of CNTs, CNS compound films by trapping the incident light. Fundamental space environmental simulation tests (SEST) were performed on the coated films, that showed promising results with reflectance values almost unaltered in the visible and NIR spectral bands, demonstrating the durability of these films as potential candidates to be used in extreme space environmental conditions. This study describes the preparation, characterization, and testing of blended CNT and CNS coatings for low-light scattering applications.

In this work, a numerical study of mixed convection flow around a 2-D top surface cooled circular cylinder is carried out using ANSYS Fluent. An FVM is used to discretize and to find the solutions of N-S and energy equations. The cooling of the cylinder surface plays a vital role in the boundary layer development and dynamics of wake past the cylinder. We have attempted to study the impact of Richardson number at a constant Reynolds number, which characterizes the surface cooling in the mixed convection flow on the aerodynamic coefficients and vortex shedding frequency. The cylinder experienced an increase in lift coefficient and shedding frequency, while coefficient of drag decreased with cooling the top surface of the cylinder.

Two series of samarium co-doped in 10 mol% Gd doped ceria Ce0.90Gd0.1O1.95(GDC10) formulated as Ce0.9-xSmxGd0.1O2-δ(CS) and Ce0.9Gd0.1-xSmxO2-δ(GS) (x = 0.0, 0.03, 0.05 0.10) were synthesized by glycine nitrate auto combustion method. The structural effects of Sm substitution in the GDC10 solid solution have been studied by X-ray diffraction (XRD) and Raman spectroscopy techniques. An increased lattice constant (5.407 A to 5.414 A) with decreasing crystallite size (28.6 nm 22.5 nm) was observed in both the Ce substituted by Sm (CS) and Gd substituted by Sm (GS) in GDC10 crystal system. The highest oxygen vacancy concentration ( V O ⋅ ⋅ = 2.65 × 1021 cm−3) was found for 10 mol % Sm and 10 mol % Gd doped ceria (Ce0.8 Sm0.1Gd0.1O1.90) composition (CS10) evaluated by spatial correlation model from Raman spectroscopy. The microhardness of the sintered pellets was investigated by Vickers hardness measurement. The highest fracture toughness was found to be 1.85 ± 0.27 MPa m1/2 for Ce substituted by 3 mol% Sm composition (CS3) among the overall compositions. The surface morphology and elemental composition of the CS and GS compositions were analyzed by FESEM. The morphology and composition of optimized electrolyte (CS10) was further analyzed by HRTEM and XPS respectively. AC impedance spectroscopy revealed that CS10 composition has an improved ionic conductivity (σ800 = 0.147 × 10−3 S‧cm−1) with significantly reduced activation energy (0.85 eV) in the temperature range of 673–1073 K under air atmosphere. A mechanism for conductivity enhancement by oxygen vacancy for CS compositions has been proposed. The effect of Sm as a secondary co-dopant in the GDC10 electrolyte was studied in detail to establish a candidate electrolyte material for operating solid oxide fuel cells in the intermediate temperature range (673–1073 K).

A non-descript dog about three years was presented with the history of vomiting for three weeks with yellow colour vomitus. Lateral survey radiography of thorax revealed elevated thoracic trachea with enlarged mediastenal lymph node and nodular lesion underneath at the level of third intercostal space. On endoscopic examination, the oesophageal mucosa was pale pink in colour with two glistening nodules in the proximal thoracic oesophagus. Histopathological examination of oesophageal nodular biopsy revealed fibrous tissue infiltrated with inflammatory cells. Coprological examination demonstrated presence of ova of Spirocerca lupi worms and the condition was diagnosed as a case of Spirocerca lupi infection. The dog was treated with doramectin, rabeprazole and ondansetron and became asymptomatic within three weeks of treatment.

The variations in the protein profile of aortic-valvular (AVE) and endocardial endothelial (EE) cells are currently unknown. The current study’s objective is to identify differentially expressed proteins and associated pathways in both the endothelial cells. We used endothelial cells isolated from the porcine (Sus scrofa) aortic valve and endocardium for the profiling of proteins. Label-free proteomics was performed by liquid chromatography-tandem mass spectrometry (LC-MS/MS). Our proteomics analysis revealed that 29 proteins were highly expressed, and 25 proteins were less expressed in the valve than the endocardial endothelium. The cell surface markers, such as CD63, ICAM1, PECAM1, PROCR, and TFRC, were highly expressed in EE. In contrast, CD44 was highly expressed in AVE. The pathway analysis showed that metabolic process-related proteins and extracellular matrix-related proteins were enriched in valves. Differential enrichment of signaling pathways was observed in the endocardium. The hemostasis function-related proteins were increased in both endothelial cells. The proteins and pathways enriched in aortic-valvular and endocardial endothelial cells revealed the distinct phenotype of these two closely related cells.

This work reports the coprecipitation synthesis and characterization of single-phase Sm3+/Sr2+/Ca2+ codoped with Gd3+ in cerium oxide formulated as Ce0.8M0.1Gd0.1O2−δ (CMGO; M = Sm3+, Sr2+, Ca2) na...

In the present study, a nanocomposite cathode comprising Fe rich La 0.6 Sr 0.4 Co 0.2 Fe 0.8 O 3-δ (LSCF) based pervoskite semiconductor oxide and Sm-Gd co-doped ceria rich Ce 0.8 Sm 0.1 Gd 0.1 O 1.90 (CSGO) in the ratio of 1:1 has been successfully synthesized by a simple glycine nitrate auto combustion method. The structural properties of the two phase nanocomposite were evaluated by X-ray diffraction and Raman spectroscopy. A detailed electrical properties of co-doped LSCF-CSGO nanocomposites have been studied with a comparison of LSCF added with 10 mol% and 20 mol% Gd singly doped ceria (LSCF-GDC10 and LSCF-GDC20) nanocomposites as a function of temperature in the range of 673–1073 K at air atmosphere by AC impedance spectroscopy. The total electrical conductivity of the co-doped LSCF-CSGO nanocomposites has been found to be 0.043 S cm −1 at 973 K which is higher than that of the LSCF composite containing singly doped compositions. The Sm co-doping in GDC phase has effectively helped to reduce the undesired electronic conduction produced in the doped ceria as the electron concentration of LSCF-CSGO was found to be − 2.62 × 10 15 cm −3 which was lower than the electron concentration of LSCF containing singly doped nanocomposite (LSCF-GDC20, − 2 ×10 16 cm −3 ) estimated by Hall-Effect measurement. The activation energy of LSCF-CSGO nanocomposite has been found to be 0.05 eV for the oxygen reduction reaction by temperature dependent Arrhenius equation. The improved electrical properties in terms of high ionic conductivity and low activation energy have been achieved through the incorporation of Sm into GDC10 electrolyte phase in LSCF nanocomposite. The combustion synthesis method has also effectively helped to produce microstructure containing large grain size (~ 6 µm) which is beneficial for enlarging triple phase boundary (TPB) area of cathodes utilized in solid oxide fuel cells (SOFC) operated at reduced/intermediate temperature (673–973 K).

A switched-capacitor (SC) voltage boost converter and its control methods for implementing dc-ac and ac-dc power conversion. The SC converter employs a switched-capacitor circuit augmented with the main converter circuit to the power source, thus providing unique features that cannot be attained by the traditional voltage-source inverter (VSI) or boost VSI. The additional features include doubling the area of the linear modulation region and eliminating both the large inductor in the boost dc-dc stage and the large filtering capacitor, which leads to a higher energy density and lower cost. The SC converter concept can be applied to all dc-ac, ac-dc, ac-ac, and dc-dc power conversions. To describe the operating principle and the control, we focus on one example: a bidirectional SC converter for dc-ac and ac-dc power conversion in electric and hybrid electric vehicles.

Multiferroic hexagonal yttrium manganese oxide (YM nO3, S1) and YM nO3/Y2O3 (S2) bilay er thin films were deposited on Si (111) substrate by the pulsed laser deposition technique. The crystal structure of both YM nO3 and YM nO3/Y2O3 bilayer thin films was studied using grazing incidence X-ray diffraction (GI-XRD). The surface morphology and elemental analysis of as-grown thin films were investigated by field emission scanning electron microscope (FESEM ) attached with energy dispersive x-ray spectroscopy (EDS). The room temperature electrical properties, leakage current versus voltage (I-V) characteristics were investigated. The XRD studies revealed that the single and bilayer YMnO3 thin films are poly crystalline and preferred oriented (004,110, and 214) hexagonal YM nO3 structure. The leakage current density of S1 and S2 thin films is measured to be 1.15x10−4 and 1.01x10−4 A/cm2 at +5V, respectively.

A computational investigation on two-dimensional surface splitted (along x-axis through 0° and 180° and obtained top surface and bottom surface for the cylinder) circular cylinder has been conducted for various Richardson number ranges −1 ≤ Ri ≤ 0 and at Reynolds number 100. The negative value of Richardson number represents cooling effect on the surface of the cylinder. The cooling of surfaces of circular cylinder affects the vortex dynamics and causes variation in aerodynamic parameters and vortex shedding frequency. This work attempts to give a clear idea on changes in vortex dynamics due to cooling of top surface and bottom surface of the circular cylinder individually. Cooling effect on the surface created unstable density layers and caused asymmetry in vortex dynamics on both top half cooled and bottom half cooled cases. Cooling of top surface shown reduction in shedding frequency while cooling of bottom surface shown increase in shedding frequency, which is exactly opposite behavior. Cooling of top surface of the cylinder is an effective drag reduction method and also found reduction in shedding frequency.

In the present study, numerical simulation was carried out for the flow around the two inline equilateral triangular cylinders at different gap ratios (G/D) for various Reynolds numbers (Re). The numerical investigations are carried out for 75 ≤ Re ≤ 200 and 0 ≤ G/D ≤ 2.5. The governing differential equations for laminar incompressible flow are discretized using finite volume method and PISO algorithm is employed to convert PDE to algebraic equation using the open-source software package. The effect of G/D ratio and Re on the non-dimensional shedding frequency Strouhal number (St) is investigated with the aid of vorticity plot and velocity profiles.

This paper presents the results of flow over square cylinder with dissimilar leading edges such as corner recession and corner arc at a Reynolds number 200. The leading edges are modified in such a way that the dimensions of the bottom leading edge are kept fixed and that of top leading edge is varied in the predefined proportions or cut ratios between 0 and 1 with respect to bottom edge. This study reveals that the flow over square cylinder with dissimilar leading edges shows an inverse relationship between Strouhal number and coefficient of drag for cut ratios less than 0.5 but beyond 0.5, both these parameters register an increasing trend.

This chapter explains the emerging trends and development of cerium oxide–based material as a potential solid electrolyte for intermediate temperature solid oxide fuel cells (IT-SOFCs) application. The new strategies and approaches toward the enhancement in the ionic conductivity of the solid electrolyte in the current literature are discussed. The influence of structural and microstructural modifications on electrical properties of the solid electrolyte has been explained from the fundamental material aspect of IT-SOFCs. The various contributing factors for ionic transport such as grain and grain boundary effect in the bulk nanostructures are described. In addition, the importance of the oxide ionic conductivity to reduce the operational temperature of SOFCs is highlighted. The ongoing research in the development and requirements of thin layer of electrolytes using both chemical and physical methods are illustrated. This chapter highlights on the key development of interlayers which can be used in conjunction with doped ceria electrolytes for IT-SOFCs. The work also reviews the recent progress, advancements, and future directions in the ceria-based electrolytes for IT-SOFCs.

Partial pulpotomy is a procedural intervention that can maintain the vitality of pulp during the management of traumatized permanent teeth with pulpal involvement.To evaluate whether partial pulpotomy can be considered a reliable conservative treatment option for treating traumatized permanent anterior teeth with pulpal involvement.A computerized systematic search was performed in PubMed, Science Direct, Cochrane, and LILACS databases from 1980 to May 2021. Five studies were included in the final analysis. Quality assessment, Meta-analysis, and Publication bias of the studies were evaluated. This systematic review was registered in PROSPERO (ID - CRD42021262031).The comprehensive Meta-Analysis Software was used. The test of the heterogeneity was analysed using Cochran's Q statistics. The Q value was 7.186 (df = 6) with a P value of 0.3 and IEvidence indicates that partial pulpotomy may be considered a reliable definitive treatment option in asymptomatic traumatized permanent anterior teeth with exposed pulp rather than total pulpotomy.

This paper studies the variations in flow characteristics over a Double Forward-Facing Step (DFFS) by considering two different Reynolds numbers (Re=100 and 200) and four different values of distance between steps (0.1, 0.15, 0.2 and 0.25 m). The results show that flow will separate and reattach in two different regions. The location and size of re-circulation zones depend on the Reynolds number. As Reynolds number is increased, the re-circulation zones before and after the step increased in their size. The re-attachment length after the second step was found increasing with increase in distance between the steps. It was found that, as the Reynolds number and the distance between the steps are increased, the 3D effects are getting more and more predominant.